1. If 'mat-form-field' is an Angular component, then verify that it is part of this module. 2. If 'mat-form-field' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message. code example
Example 1: 'mat-form-field' is not a known element
@NgModule({
imports: [
...
MatFormFieldModule,
MatInputModule,
...
]
})
Example 2: 'mat-label' is not a known element:
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatInputModule } from '@angular/material/input';
@NgModule({
imports: [
MatFormFieldModule,
MatInputModule
]
})
export class CommonWidgetsModule { }
Example 3: 'mat-form-field' is not a known element:
@NgModule({
imports: [
MatButtonModule,
MatFormFieldModule,
MatInputModule,
MatRippleModule,
]
....